1. Field of the Invention
This invention relates to an electronically controlled suspension system which is designed to take on an automatic mode when the engine key switch is turned on.
2. Description of the Prior Art
Electronically controlled automobile suspensions have been proposed that are electronically switched into a hard and a soft condition. This type of electronically controlled suspensions are equipped with a mode selection switch that permits an alternative choice between a hard mode that puts the suspension in the hard state and an automatic mode (hereinafter abbreviated as "auto mode") that automatically puts the suspension into the soft or hard state depending upon the conditions of automobile. When the auto mode is chosen, the suspension is normally in the soft state. It is only when a predetermined condition or conditions are met (for example, when the car speed exceeds a given limit) that the suspension automatically switches into a hard state. This provides a comfortable ride. The hard mode is chosen where a hard suspension is preferred as in running over such bumpy roads as those passing over mountains or by a driver who prefers his car to run at all times on a hard suspension rather than on a soft one.
When a car having this type of electronically controlled suspension equipped with a mode selection switch is started by turning on the engine key switch (KEY-ON), however, the car will continue to run on the suspension kept in a hard state if the mode selection switch is set to the hard mode, unless or until the driver turns the switch to the auto mode. In this state, even with a driver who prefers the more comfortable auto mode to the hard mode, the car will run on the hard suspension even under such road conditions as might probably be run with the soft suspension if the switch were set to the auto mode, unless the driver notices that the switch is at the hard mode, putting the driver to great discomfort.